Lee Collet die adjusting

[Char-Gar]

In the recent issue of The Fouling Shot, John Alexander write:

" ...the Lee Collet die which can be adjusted to achieve a range of neck diameter."

And,

"Additionally the inside diameter can be varied to achieve the neck tension required."

I have some Lee Collet dies, but don't understand the ins and outs of them. So how can they be adjusted to achieve a range of neck diameters which of course will change the inside diameter?

Will somebody who has actually done this, please explain it to me in simple step by step instructions.

Thank you...

[462]

Yep, I adjust the die -- in or out -- till the desired diameter/tension is achieved. I use an inside micrometer to measure the neck's inside diameter, though I suppose it could be accurately enough determined with a sized boolit.

[Maven]

"I have some Lee Collet dies, but don't understand the ins and outs of them. So how can they be adjusted to achieve a range of neck diameters which of course will change the inside diameter?"

Char-gar, I read John's article yesterday as well and wondered about that assertion as well. There was an article in TFS several years ago, which said you could shorten the very top of the collet by ~0.03" so as to leave the mouth of the neck unsized, making belling unnecessary. I tried that, but it didn't work for the .243Win. collet die set I have. OTOH, the .30-06 collet die set I have (almost as old as the one John has), doesn't size my '06 case mouths down so severely that I always have to use the M-die.

Btw, my experience with M-dies has been the opposite of John's too. I haven't found a causal link between using one (for all the calibers I reload for) and hardened case necks.

[45 2.1]

Basic adjustments are made by up or down of the die or by changing out the decapping stem to the diameter you want. The top of the collect can be shortened below the case neck end or inside belled so the neck end will have sufficient bell left to accept a cast boolit without damage.

[popper]

Lee NS and rifle FCD work on the principle of 4 finger crimping. The NS inside-the-neck shaft is to provide a minimum neck diameter for the crimp and decap. The ONLY way this design can give accurate repeatable NS is if the shaft is sized to the proper neck ID, allowing for spring back. Anything else is a SWAG. Does it work? Sometimes. The FCD does what it is supposed to do, the case mouth is bent into a crimp, which may damage the CB.

[Maven]

popper, Char-gar, 45 2.1, and I were referring to John Alexander's discussion of the Lee COLLET die, not their FCD...or did I misunderstand the original post?

[Char-Gar]

No, you did not misunderstand, it is the collet die. If this works as Alexander says, it would be the answer to lots of our issues with neck expanding and bullet tension. My gut tells me, it just can't be that easy, but maybe it is.

[L Ross]

Char-Gar, for me it really has been that easy, I've been doing it for several years in 30-06, 8 mm, and 7 m/m. I just think of it as partial neck sizing. To address poper's legitimate concerns I also run the brass over a Lyman M die. It elimintes the need to lubricate the brass and subsequently remove the lube. I often run out to the bench, fire a few come back into the loading disaster area, run them thru the collet, the M, prime, powder, seat and walk back to the bench and shoot 'em again just a few minutes later.
I feel I am really working my brass very minimally, but a still anneal after about 5 cycles.

Duke

[Char-Gar]

I think we are wandering afield here. The ever popular thread drift effect is about to take over. To those of you who have not read John Alexander's article in The Fouling Shot (Cast Bullet Association Journal", here is the jist of it.

1. A Lee Collet neck sizing die can be adjusted to give you various outside neck dimensions and thus inside neck dimensions as well. This allow a person to use cast bullets of various diameters to give proper neck tension.

2. The case mouth is reamed with a taper reamer allowing the bullet to enter the case without shaving lead.

3. Thus, there is no need for an M-Die to expand, case lubricant as the Collet die does not require lubricant.

4. So, just neck size in your adjusted Collet dies for whatever bullet you are using, load and fire, and that is that. Cases thus used don't over work the brass in the case neck and thus eliminates work hardening of the brass.

It is too this article and process, I address my question.

[geargnasher]

In the recent issue of The Fouling Shot, John Alexander write:

" ...the Lee Collet die which can be adjusted to achieve a range of neck diameter."

And,

"Additionally the inside diameter can be varied to achieve the neck tension required."

I have some Lee Collet dies, but don't understand the ins and outs of them. So how can they be adjusted to achieve a range of neck diameters which of course will change the inside diameter?

Will somebody who has actually done this, please explain it to me in simple step by step instructions.

Thank you...

I have not read the article, but I am familiar with the process so described and have recommended it here many times.

All you do is adjust the die BODY so that the collet crimper doesn't swage the neck all the way down against the mandrel. In .308 the mandrel/decapper is .307" in diameter. This is a delicate adjustment because you're using the 7/8x14 threads to make a very fine adjustment to the collet swaging depth, and about half a turn on the die body goes from no sizing (.342-3" OD) to fully sized (.334") in both of my .30-calibers, I haven't measured the others I have (.35 Rm and .270 Win).

You will still need to size below desired and expand back up with a quality expander die in order to have consistent boolit pull unless you size fully against the mandrel. This is no fault of the die itself, but of the neck-sizing process which varies the ID and thus tension of the neck on the boolit depending on neck thickness, consistency, and state of anneal. But the die is cheap, infinitely adjustable, and will keep you from overworking your brass or having to buy a NS die body and a variety of expensive OD bushings to get what you want.

Several people that I know have made custom, oversized mandrels for the Lee die, and I think even Lee themselves offers this as a custom service. Lapping the collet fingers to the larger OD helps also with the larger radius and keeping the shoulder supported.

Gear

[geargnasher]

Simultaneous post!

Anyone who says you don't need to "clean up" the final neck ID with a good expander (NOT the worthless, *** "M" die, but a real, one-step expander like RCBS makes) either lives in a perfect world or is being a bit too optimistic. Even with matched brass, uniform case necks, and consistent anneal, neck tension can be a bit inconsistent from a mere outside resize. Even if you just drag the neck over a Lee mandrel (like .303 British for all .30 caliber cases using .311" boolits) that will be good enough, but if the article says you don't need to do anything to uniform the ID of the necks the writer probably either never tested ammo made the way he suggested, or doesn't have very high accuracy standards.

Gear

[Char-Gar]

Here is the jist of the article to which I was address my question;

1. Adjust your Collet neck sizing die to give the outside neck size you want that will give you the proper inside diameter for the bullet tension you want. No additional neck sizing is required.

2. Ream the cast mouth to start the bullet without shaving using a tapered reamer.

3. That is it. No lube, no M-die, no expander, no nothing.

This is supposed to produce accurate cast bullet ammo without work hardening the brass in the case necks.

As an aside, I use a Vickerman stright line bullet seater with a custom seating chamber for cast bullets. I can use a deburring tool on the case mouth and seat the bullet with no shaving and without belling the case or using the top step of an M-die.

[geargnasher]

Here is the jist of the article to which I was address my question;

1. Adjust your Collet neck sizing die to give the outside neck size you want that will give you the proper inside diameter for the bullet tension you want. No additional neck sizing is required. My experienced answer to your question is that, while it's a nice idea, it doesn't really work that way unless your necks are in a PERFECT condition. In the real world you will find that the collet NS die will leave inconsistent case neck ID unless you size about a thousandth BELOW what you want and expand back up for uniformity. This DOES prevent overworking the brass compared to using conventional FL sizing dies and an M die expander. For example, if using .311" boolits in a .30 caliber, I adjust the die to size my necks enough for an ID of .308-9" and run a .310" expander through them to uniformly give me .3095-8" ID depending on neck hardness of that particular lot.

2. Ream the cast mouth to start the bullet without shaving using a tapered reamer. VLD chamfer tools work just fine.

3. That is it. No lube, no M-die, no expander, no nothing. There is no free lunch. This will sorta work like the article says, especially with a true, straight-line seating die set up for your exact boolit diameter, but the collet NS die will not give precision to the ID of the necks to more than +/- a half-thousandth in a box of 50. If that's good enough for you, great. Otherwise, plan on using an inside-type expander to just kiss the necks on the inside and pull them back perfectly round and uniform

This is supposed to produce accurate cast bullet ammo without work hardening the brass in the case necks. Accurate is relative. Yes, the process DOES reduce overworking and hardening of the necks, that's why I've been recommending it to people.

As an aside, I use a Vickerman stright line bullet seater with a custom seating chamber for cast bullets. I can use a deburring tool on the case mouth and seat the bullet with no shaving and without belling the case or using the top step of an M-die.

Now, the IMPORTANT part about NS'ing a thousandth under final ID and expanding back that last thousandth for uniformity: You MUST use an RCBS expander die or you're farting in the wind. Lyman's "M" dies are designed on a different concept, and one fundamentally unsuited to cast boolits. The RCBS dies have a spud with a half-degree taper and a large bellmouth shank, and they're long enough in rifle calibers to expand or true the whole neck. Just like an RCBS pistol die expander/belling spud, you can adjust them for no bellmouth, a lot of it, or anything in between, but they have no goofy steps or starter shanks on them, just a real expander spud that can be had in .001" increments in many calibers.

Again, this is the voice of experience. I've been messing with these Lee collet NS dies for a long time and have observed the variables and the accuracy changes associated with different user techniques. Until my recent discovery of the RCBS expander die, I never got the accuracy I was looking for with cast boolits and the Lee collet die. The Lee die is a great tool, but we're using it outside it's design parameters so unless you get a custom, oversized mandrel to fit your boolit size like I mentioned above, you'll need something to uniform the ID of the neck after sizing for best accuracy.

Gear

[45 2.1]

Now, the IMPORTANT part about NS'ing a thousandth under final ID and expanding back that last thousandth for uniformity: You MUST use an RCBS expander die or you're farting in the wind. Lyman's "M" dies are designed on a different concept, and one fundamentally unsuited to cast boolits. The RCBS dies have a spud with a half-degree taper and a large bellmouth shank, and they're long enough in rifle calibers to expand or true the whole neck. Just like an RCBS pistol die expander/belling spud, you can adjust them for no bellmouth, a lot of it, or anything in between, but they have no goofy steps or starter shanks on them, just a real expander spud that can be had in .001" increments in many calibers.

Again, this is the voice of experience. I've been messing with these Lee collet NS dies for a long time and have observed the variables and the accuracy changes associated with different user techniques. Until my recent discovery of the RCBS expander die, I never got the accuracy I was looking for with cast boolits and the Lee collet die. The Lee die is a great tool, but we're using it outside it's design parameters so unless you get a custom, oversized mandrel to fit your boolit size like I mentioned above, you'll need something to uniform the ID of the neck after sizing for best accuracy.

Gear

Hee hee hee............ I won't do a bit of good to tell them that.

[popper]

you'll need something to uniform the ID of the neck after sizing for best accuracy. Totally agree, finding the right size is the problem. I'd like to see someone make a M spud like the RCBS, in .001 or .0005" increments, as a set, per caliber. Probably 4 per cal. I do like the screw-in M and cost should be much less. A set would allow matching to various alloys, playing with diff neck tension etc. without needing to get a 'special' or ordering several at different times. Kinda like shotgun chokes, just swap out for what you need. Same goes for Lee push-through sizers.